Recently, miniature electronic devices such as cellular phones, micro video cameras, and portable information terminals can send and receive data to and from desk top personal computers. These miniature electronic devices are mounted with a socket which is used as an interface connector (or an I/O connector) for sending or receiving data.
In many cases, electronic devices with the socket use a connection base designated as a cradle (also referred to as a docking station) for sending or receiving data.
The cradle is mounted with a plug thereon and is connected to a cable by which the cradle and a desk top personal computer are connected to each other. On the other hand, an electronic device such as portable information terminals has a socket, and the socket disposed on the electronic device can be connected to the plug mounted on the cradle to secure high-speed data transfer between the electronic device and the desk top personal computer. One of the simplest forms of the cradle is a charger for cellular phones.
Additionally, when the socket disposed on the electronic device and the plug mounted on the cradle are not connected to each other, contacts provided within the socket is exposed unprotected. As a result, the contacts may be damaged by handling or dust.
To solve this problem, a socket having a cap or a cover for covering the socket so as to protect contacts arrayed in the socket from dust or handling has known.
Another dustproof connector by providing a shutter, instead of a cap or a cover for covering the socket has been provided (Japanese Unexamined Patent Publication No. 2001-351747). The connector disclosed in the Patent Document comprises a socket comprising a shutter which is closed to cover contacts disposed within the socket when a plug is not inserted into the socket. Thus, when a plug is not inserted into the socket, the contacts are protected from dust, whereas when a plug is inserted, the shutter is opened by pushing back the plug, thereby enabling the plug and the socket to come into contact with each other.
However, the cap or the cover should be removed from the socket having the cap or the cover, every time a plug is connected to the socket, making the connection more troublesome. Furthermore, there is a fear that the cap or the cover may be lost.
The plug mounted on a cradle is generally a multi-polar dual in-line plug having two rows of contacts. In the dual in-line plug, the contacts arrayed in two lines are surrounded by insulating fixed vertical walls protecting the contacts from being handled. Such a dual in-line plug is called four-wall shrouded, thereby having a large outer size.
However, electronic devices (micro video cameras, for example) to be connected to a cradle equipped with a dual in-line plug are increasingly being reduced in size. For this reason, it has been sought to miniaturize a dual in-line socket which can be connected to a dual in-line plug and can be attached to the aforementioned electronic devices.
However, the shutter provided within the socket of the dustproof multi-conductor connector disclosed in the aforementioned Patent Document is a folding retractable shutter composed of a plurality of shutter components, and the multi-conductor connector also has a locking mechanism. These features inevitably increase the outer size, making the socket unsuitable as a micro socket for use in an interface, which is now being sought.
In order to solve the aforementioned problems, the present invention has an object of providing a miniature multi-polar socket which can prevent contacts thereof from being exposed unprotected all the time.